diff --git a/qualdev/debug8.ts b/qualdev/debug8.ts
new file mode 100644
index 0000000000000000000000000000000000000000..29907511adcf17909abb93bf746d90b5b110e736
--- /dev/null
+++ b/qualdev/debug8.ts
@@ -0,0 +1,26 @@
+let n = 5;
+console.log(deb8(n));
+
+function deb8(n: number): number {
+    if (n === 0) {
+        return 1;
+    }
+    let valeur = n * deb8(n - 1);
+    return valeur;
+}
+
+
+/* Nom fonction factorielle 
+on peut modifier le let valeur pas un return
+
+deb8(1) = 1 * 1 = 1
+
+deb8(2) = 2 * 1 = 2
+
+deb8(3) = 3 * 2 = 6
+
+deb8(4) = 4 * 6 = 24
+
+deb8(5) = 5 * 24 = 120
+
+*/
\ No newline at end of file